elastin and Edema

The pre-Descemet's layer/Dua's layer, also termed the Dua-Fine layer and the pre-posterior limiting lamina layer, lies anterior to the Descemet's membrane in the cornea, is 10 μm (range 6-16) thick, made predominantly of type I and some type VI collagen with abundant elastin, more than any other layer of the cornea. It has high tensile strength (bursting pressure up to 700 mm of Hg), is impervious to air and almost acellular. At the periphery it demonstrates fenestrations and ramifies to become the core of the trabecular meshwork, with implications for intraocular pressure and glaucoma. It has been demonstrated in some species of animals. The layer has assumed considerable importance in anterior and posterior lamellar corneal transplant surgery by improving our understanding of the behaviour of corneal tissue during these procedures, improved techniques and made the surgery safer with better outcomes. It has led to the innovation of new surgical procedures namely, pre-Descemet's endothelial keratoplasty, suture management of acute hydrops, DALK-triple and Fogla's mini DALK. The discovery and knowledge of the layer has introduced paradigm shifts in our age old concepts of Descemet's membrane detachment, acute corneal hydrops in keratoconus and Descemetoceles, with impact on management approaches. It has been shown to contribute to the pathology and clinical signs observed in corneal infections and some corneal dystrophies. Early evidence suggests that it may have a role in the pathogenesis of keratoconus in relation to its elastin content. Its contribution to corneal biomechanics and glaucoma are subjects of current investigations.

Topics: Corneal Transplantation; Descemet Membrane; Edema; Elastin; Glaucoma; Humans; Keratoconus

Topics: Anti-Bacterial Agents; Atrophy; Blepharoptosis; Doxycycline; Edema; Elastin; Female; Humans; Tacrolimus; Treatment Outcome; Young Adult

Composition changes of extracellular matrix (ECM) can lead to functional disorders of the upper airways (UA). The aim of this study was to systematically measure both the association patterns and the correlation degree between tissue composition parameters in UA inflammatory diseases.. Nasal samples were obtained from patients with chronic rhinosinusitis with (CRS+NP), without nasal polyps (CRS), with post-operative adhesions (S) and normal nasal mucosa (NM). A reproducible semi-quantitative method, which takes epithelial and lamina propria damages into account was applied for haematoxylin and eosin, alpha-smooth muscle actin, reticulin, elastin, laminin and collagen type IV stainings.. The most severe cases of epithelial shedding have been found in a significant higher amount in CRS+NP when compared with NM. The most severe cases of inflammatory reaction were mainly found in CRS+NP. CRS+NP had significantly more severe cases of oedema than NM. Excluding elastin, networks in other ECM proteins were found modified in fibrotic fields but to a lesser extend in oedematous regions in all conditions.. Although non specific, oedema in the lamina propria is a key-feature of CRS+NP, while fibrosis, massively present in CRS and S, affects profoundly the distribution of ECM proteins in these areas.

Topics: Actins; Adolescent; Adult; Chronic Disease; Collagen Type IV; Connective Tissue; Edema; Elastin; Extracellular Matrix Proteins; Female; Fibrosis; Humans; Immunohistochemistry; Laminin; Male; Middle Aged; Nasal Mucosa; Nasal Polyps; Reticulin; Rhinitis; Sinusitis; Young Adult

Poly(L-valine-L-proline-L-alanine-L-valine-L-glycine) (VPAVG) is a new kind of proteinaceous polymer belonging to the Elastin-like family. These polymers are based on the recurrence of certain short peptide monomers that are considered as "building blocks" in the natural elastin. This smart thermoresponsive polymer has the ability to self-associate at physiological temperature to form aggregates with about 60% in water. This ability can be harnessed to prepare microparticles loaded with an active substance. The aim of this report is to evaluate, from the results of the experiment conducted, the biocompatibility of microparticles prepared from poly(VPAVG). We have studied the cytotoxic effects of microparticles, edema formation after subcutaneous injection (1 and 2.5 mg) in rats (n = 6), and also intraocular tolerance after the intravitreal injection of 2.5 mg of poly(VPAVG) microparticles into pigmented rabbits (n = 12). The polymer did not induce any cytotoxicity or nonspecific depression of cellular respiration on macrophages under the range of polymer concentrations investigated in this study (20, 30, 40, and 60 mg/mL). We observed no inflammatory response to microparticles after subcutaneous injection in the hind-paw of rats, with no significant differences between the control group (PBS) and experimental groups. Anterior and posterior segment signs were evaluated after intraocular injection of poly(VPAVG) microparticles. Only a few eyes (2/11) of the experimental group presented inflammation signs at day 28 postinjection. Nevertheless, 45% (5/11) of the eyes receiving microparticles showed tractional retinal detachment. The results observed in this work suggested certain fibroblastic activity induced by poly(VPAVG) microparticles after their intraocular injection.

Topics: Alanine; Amino Acid Sequence; Animals; Biocompatible Materials; Cell Survival; Conjunctivitis; Edema; Elastin; Glycine; Macrophages, Peritoneal; Mice; Microscopy, Electron, Scanning; Molecular Weight; Peptides; Proline; Valine; Vitreous Body; X-Ray Diffraction

Blepharochalasis is a rare condition characterized by recurrent episodes of eyelid edema lead to an atrophic eyelid skin with fine wrinkles and peculiar bronze discoloration. A 32-year-old female presented with loose and redundant skin of the bilateral eyelids. We diagnosed her disease as blepharochalasis by clinical features and by disappearance of elastic fibers from the dermis in the biopsied specimen. Because elastic fibers diminish in the late phase of blepharochalasis, we performed RT-PCR to analyze the mRNA expression of elastin, a major component of elastic fiber. Elastin mRNA expression in the patient's cultured fibroblasts had not decreased compared with that in the control fibroblasts. This result suggests that environmental factors or other matrix components of elastic fibers may be involved in the loss of elastic fiber.

Topics: Adult; Atrophy; Diagnosis, Differential; Edema; Elastin; Eyelid Diseases; Female; Fibroblasts; Gene Expression; Humans; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger

Human leukocyte elastase (HLE) is a proteinase capable of degrading a variety of proteins. Under normal circumstances, the proteolytic activity of HLE is effectively controlled by its natural inhibitors. However, an imbalance between elastase and its endogenous inhibitors may result in several pathophysiological states such as chronic obstructive pulmonary disease, asthma, emphysema, cystic fibrosis, and chronic inflammatory diseases. It is anticipated that an orally active HLE inhibitor could be useful for the treatment of these diseases. 2-(9-(2-Piperidinoethoxy)-4-oxo-4H-pyrido[1,2-a]pyrimidin-2-yloxymethyl)-4-(1-methylethyl)-6-methoxy-1,2-benzisothiazol-3(2H)-one-1,1-dioxide (SSR69071) is a potent inhibitor of HLE, with the inhibition constant (K(i)) and the constant for inactivation process (k(on)) being 0.0168 +/- 0.0014 nM and 0.183 +/- 0.013 10(6)/mol sr, respectively. The dissociation rate constant, k(off), was 3.11 + 0.37 10(-6)/s. SSR69071 displays a higher affinity for human elastase than for rat (K(i) = 3 nM), mouse (K(i) = 1.8 nM), and rabbit (K(i) = 58 nM) elastases. Bronchoalveolar lavage fluid from mice orally treated with SSR69071 inhibits HLE (ex vivo), and in this model, SSR69071 has a dose-dependent efficacy with an ED(50) = 10.5 mg/kg p.o. SSR69071 decreases significantly the acute lung hemorrhage induced by HLE (ED(50) = 2.8 mg/kg p.o.) in mice. Furthermore, SSR69071 prevents carrageenan- (ED(30) = 2.2 mg/kg) and HLE-induced (ED(30) = 2.7 mg/kg) paw edema in rats after p.o. administration. In conclusion, SSR69071 is a selective, orally active, and potent inhibitor of HLE with good penetration in respiratory tissues.

Topics: Algorithms; Animals; Bronchoalveolar Lavage Fluid; Carrageenan; Cyclic S-Oxides; Dose-Response Relationship, Drug; Edema; Elastin; Enzyme Inhibitors; Hemorrhage; Humans; Hydrolysis; Kinetics; Leukocyte Elastase; Male; Mice; Oligopeptides; Rabbits; Rats; Thiazoles

A neutrophil elastase inhibitor FR901277 was examined for its inhibitory effect on degradation of natural substrate elastin in vitro, and on acute inflammatory states and pulmonary emphysema in vivo.. Elastin-congo red was used as a substrate for elastin degradation assay. Paw edema in male C57BL mice (6 weeks old) and pulmonary hemorrhage in female golden hamsters (5 weeks old) were induced by topical injection of human neutrophil elastase (HNE). Pulmonary emphysema in male golden Syrian hamsters (10 weeks old) was provoked by intratracheal instillation of porcine pancreatic elastase. In all in vivo experiments. FR901277 was administered prior to elastase treatment.. Elastin degradation by HNE was monitored spectrophotometrically with elastin-congo red. Foot swelling was measured by calipers. Pulmonary hemorrhage was assessed by hemoglobin concentration in bronchoalveolar lavage fluid. As emphysematous parameters, quasi-static lung compliance and vital capacity were measured.. FR901277 inhibited HNE-induced elastin degradation. Systemic treatment with FR901277 significantly inhibited paw edema and pulmonary hemorrhage. Intratracheal treatment with FR901277 significantly ameliorated changes in pulmonary function.. These results suggest that FR901277 inhibits the elastase activity potently both in vitro and in vivo, and that elastase may play a role at least in part in pathogenesis of pulmonary emphysema.

Topics: Amides; Animals; Cricetinae; Edema; Elastin; Enzyme Inhibitors; Female; Hemorrhage; Humans; Inflammation; Leukocyte Elastase; Lung Diseases; Male; Mesocricetus; Mice; Mice, Inbred C57BL; Pancreatic Elastase; Pulmonary Emphysema; Swine

The aim of this study was to investigate prospectively the epithelialization process in the healing temporalis myofascial flap (TMF). Eight cats underwent maxillectomy and immediate reconstruction with TMF. They were killed at the determined time and the reconstructed maxillae were processed for examination by light microscopy and scanning electron microscopy. Results revealed that epithelialization of the healing TMF was initiated by hyperplastic changes followed by active migration of epithelial cells deriving from the wound margins. The partial maxillectomy wound was completely covered by a smooth oral mucosa at postoperative week 24. The mucosa had histological and ultrastructural features different from normal palatal mucosa.

Topics: Animals; Cats; Cell Movement; Collagen; Connective Tissue; Edema; Elastin; Epithelium; Fascia; Granulation Tissue; Hyperplasia; Inflammation; Keratins; Lymphocytes; Macrophages; Maxilla; Microscopy, Electron, Scanning; Mouth; Mouth Mucosa; Plasma Cells; Prospective Studies; Regeneration; Surgical Flaps; Temporal Muscle; Wound Healing

Elastic fibers required to maintain bronchial patency during ventilation may be damaged in asthma as a result of repair following inflammation or stretching during exacerbations. Fifteen normal subjects and 40 asthmatics of variable severity were studied. Bronchial biopsies were obtained from a subsegmental bronchus using a flexible bronchoscope. The elastic fibers were examined using orceine-eosine sustaining and/or immunohistochemistry with two monoclonal antibodies against elastin or transmission electron microscopy (six asthmatics and four control subjects). Orceine-eosine staining revealed that most normal subjects had normal fibers throughout the submucosa whereas of the 21 asthmatics analyzed only three had a normal superficial elastin network. In five patients, elastin had virtually disappeared. In the remaining patients, fibers appeared fragmented. The deeper layer of elastic fibers was abnormal in 17 asthmatics, fibers being patchy, tangled, and thickened. The fragmentation of the superficial network of elastic fibers shown in asthmatics was confirmed by immunohistochemistry. Electron microscopy studies suggested that the elastinolytic process and fragmentation of elastic fibers occurred in asthmatics. Elastinolysis occurs in the airways of asthmatics possibly as a result of repair elicited by chronic inflammation. Mechanical stretch induced by breathing and edema may lead to the fragmentation of fibers in asthmatic airways.

Topics: Adult; Antibodies, Monoclonal; Asthma; Biopsy; Bronchi; Bronchitis; Bronchoscopes; Case-Control Studies; Coloring Agents; Edema; Elastic Tissue; Elastin; Eosine Yellowish-(YS); Fluorescent Dyes; Humans; Immunohistochemistry; Microscopy, Electron; Middle Aged; Oxazines; Respiratory Mechanics

The mechanically important constituents of swelling tissues are fibers embedded in an osmotically active fluid. The tissues' response to external loading is the sum of contribution of the axial stresses in the fibers and of the fluid pressure. The fluid osmotic properties play a key role in determining its equilibrium response. The present study examines the conditions under which the elastic response of tissues as modeled by structural constitutive equations, is thermodynamically plausible. The analysis shows that plausibility is ensured if the fibers' axial force increases monotonically with stretch and if the fluid osmotic pressure increases convexly with concentration. Published data shows that both conditions prevail in swelling tissues. Plausibility considerations seem to pose no specific restrictions on the structure of the tissues' fibrous network. It is thus concluded that in swelling tissues, structural constitutive formulation is compatible with thermodynamically plausible response.

Topics: Animals; Anisotropy; Collagen; Edema; Elasticity; Elastin; Humans; In Vitro Techniques; Models, Biological; Osmosis; Stress, Mechanical; Thermodynamics

Groups of Fischer-344 rats were exposed to either filtered air, 0.4, 1.4, or 4.0 ppm acrolein for 62 days (6 h/day, 5 days/week). Mortality was observed only in the 4.0 ppm chamber, where 32 of 57 male rats died, but none of the 8 exposed females died. The lungs of the 4.0 ppm group were heavier than those of the larger control animals. Relative to controls, there was a 20% increase in total dry lung weight while the percent dry weight decreased 1.5% in the high dose group. This increased dry weight and the absence of significant changes in the DNA and protein content per unit dry weight indicated that the greater lung weight observed in this group was in part due to increased cellularity. Lung connective tissue content was increased as a result of subchronic acrolein exposure. The amount of elastin per unit dry weight was 173% of control values in the animals exposed to 4.0 ppm acrolein. Collagen levels were elevated in both the 1.4 and 4.0 ppm groups, 113 and 137%, respectively, of control values. Histologically, the 4.0 ppm animals demonstrated bronchiolar epithelial necrosis and sloughing, bronchiolar edema with macrophages, and focal pulmonary edema. Exposure related lesions were observed in only 3 of the 31 rats examined from the 1.4 ppm chamber and in none of the animals exposed to 0.4 ppm acrolein.

Topics: Acrolein; Aldehydes; Animals; Body Weight; Collagen; DNA; Edema; Elastin; Female; Kinetics; Lung; Lung Diseases; Male; Necrosis; Organ Size; Proteins; Rats; Rats, Inbred F344

Metallic copper has been shown to possess anti-inflammatory activity in the carrageenan foot paw edema of the rat, when applied in the form of an implant. The implant was installed two months before the edema was induced. It is postulated that the anti-inflammatory activity is due to dissolved copper from the implant.

Topics: Animals; Anti-Inflammatory Agents; Collagen; Copper; Drug Implants; Edema; Elastin; Male; Rats; Rats, Inbred Strains; Time Factors

Topics: Aminopropionitrile; Animals; Aorta, Abdominal; Arteries; Body Weight; Collagen; Disease Models, Animal; Edema; Elastin; Female; Ferrocyanides; Haplorhini; Hemorrhage; Hemosiderosis; Iliac Artery; Lathyrism; Macaca; Male; Sternum; Thoracic Arteries